Minimise product loss in filtration

[acewolf187]

Hi,

Can anyone help me with this problem:

Batch of liquid product in elevated tank needs to be filtered through plate and frame filter to barrels. Currently, gravity is used to drive the liquid through the filter but there's usually some left in the filter and pipework afterwards and I need to recover as mush as possible.
Flushing the line with water helps push some of the product out but after recovering about 10kg out of 50kg, the water dilutes the product and I have to stop.

So far, here's what I've come up with, what do you think:

- Blowing air through the filter inlet pipe
- Suction pump at filter outlet with tank open to atmosphere
- Suction pump at filter outlet with tank discharge valve shut (I'm not sure about this because pipeline wasn't designed for vacuum, will small vacuum (of about 0.5bar) help without doing damage?

I would like to hear all your ideas and experience in this area.

 

[cloa]

What liquid product? What filter?

http://www.eng-tips.com/threadminder.cfm?pid=1529

Use translation assistance for Engineers forum

Note the rules include No Student posting

 

[acewolf187]

Ethylene dichloride. Plate and frame filter press.

 

[bimr]

Why don't you recycle the pipe contents into the next batch?

 

[LittleInch]

Isn't this just a piping and filter layout issue? Why can't you drain the clean side of the filter down if you want to squeeze every last drop out? It's rather difficult to advise further without some more details, but blowing and sucking anything out has a number of problems and is unlikely to drain your system completely.

for some more help you need to provide a layout sketch of you pipework and filter and/ or some photos

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[itdepends]

Air blows at the end of a filtration cycle are commonly included in plate and frame filters.

However given you are only using gravity to drive your filtration, do you really need a pressure filter? A vacuum filter would be cheaper, simpler, and may give higher liquor recovery.

As a chem eng/metallurgist the first part of any answer I give starts with "It Depends"